Rotating systems can have enough rotating energy (i.e. inertia) to cause significant machine damage during a jam-up or system crash. This inertia varies based on the RPM and rotating mass for each application. A high mass low speed application could do more damage than a low mass high speed one during a crash. In order to prevent damage, a torque limiter, which is basically a mechanical fuse, is used to shut down the machine and allow the rotating energy to dissipate without causing excessive damage.
Different types of torque limiters are currently being used in the industry, namely disconnect, shear pin, synchronous magnetic, ball detent, pawl and spring, etc.
The only type of torque limiters that allow for the dissipation of rotation energy through friction is the disconnect types (i.e. torque limiting clutches) who “wait” for the torque to diminish to a predetermined level before reengaging.
The main limitations with the existing disconnect type torque limiters are that they are cumbersome (vs. torque capacity) and typically cannot be engaged or disengaged manually. Furthermore, they do not actively dissipate rotational energy.
Accordingly, there is a need for a torque limiting clutch that is compact, can be engaged or disengaged manually and dissipates rotational energy.